1 files changed, 45 insertions, 0 deletions
diff --git a/tests/ui/abi/extern/extern-call-scrub.rs b/tests/ui/abi/extern/extern-call-scrub.rs
new file mode 100644
index 000000000..ff33cf31a
--- /dev/null
+++ b/tests/ui/abi/extern/extern-call-scrub.rs
@@ -0,0 +1,45 @@
+// run-pass
+#![allow(unused_must_use)]
+// This time we're testing repeatedly going up and down both stacks to
+// make sure the stack pointers are maintained properly in both
+// directions
+
+// ignore-emscripten no threads support
+#![feature(rustc_private)]
+
+extern crate libc;
+use std::thread;
+
+mod rustrt {
+    extern crate libc;
+
+    #[link(name = "rust_test_helpers", kind = "static")]
+    extern "C" {
+        pub fn rust_dbg_call(
+            cb: extern "C" fn(libc::uintptr_t) -> libc::uintptr_t,
+            data: libc::uintptr_t,
+        ) -> libc::uintptr_t;
+    }
+}
+
+extern "C" fn cb(data: libc::uintptr_t) -> libc::uintptr_t {
+    if data == 1 { data } else { count(data - 1) + count(data - 1) }
+}
+
+fn count(n: libc::uintptr_t) -> libc::uintptr_t {
+    unsafe {
+        println!("n = {}", n);
+        rustrt::rust_dbg_call(cb, n)
+    }
+}
+
+pub fn main() {
+    // Make sure we're on a thread with small Rust stacks (main currently
+    // has a large stack)
+    thread::spawn(move || {
+        let result = count(12);
+        println!("result = {}", result);
+        assert_eq!(result, 2048);
+    })
+    .join();
+}